Flame hardener

ABSTRACT

Flame hardening method and apparatus for tempering gear teeth and the like which comprises quench means for rapidly cooling selected ones of the gear teeth to a temperature which avoids the formation of decomposition products, and a heat source spaced from the quench means for raising the temperature of selected ones of the gear teeth to a value which promotes the formation of an austenitic structure. Mount means rotatably support the gear with selected ones of the circumferentially extending teeth being placed in heat transfer relationship with the heat source and the quench. Index means rotate the gear an amount which moves one gear tooth from the heat source to the quench means in a manner whereby all of the teeth of the gear must be treated one time before any tooth can be treated a second time.

United States Patent 1191 Carrigan lll] 3,891,19

[ June 24, 191

[ FLAME HARDENER [75] inventor: [73] Assignee: Vance Industries, lnc.. Odessa. Tex.

[22] Filed: Oct. 15, 1973 [2!] Appl. No.: 406,141

[52] US. Cl. 266/4 A: l48/l47; 266/5 F; t 266/23 R [5 l] Int. Cl C216 9/32 [58] Field of Search 266/4 R. 4 A. 4 F. 5 F; big/144; I45. l46, I47

[56] References Cited I UNITED STATES PATENTS l.768.l 59 6/l930 Shorter et ul..; 266/4] 2.l 32.l l0 10/1938 Holler 266/5 F 2.l99.3 I 3 4/1940 Holler ct nl. 266/5 F FOREIGN PATENTS OR APPLICATIONS 227.296 I925 United Kingdom 266/4 F 303.l96 I928 United Kingdom l48/l47 329054 I930 United Kingdom 266/4 F 626.464 l936 Germany 8/147 446.821 l936 United Kingdom 148/147 630.844 1936 Germany 266/4 F James David Carrigan, Odessa. Tex.'

Primary Examiner-Roy Lake I Assistant Examiner-Paul' A. Bell Attorney. Agennor Firm-Marcus L. Bates [57] ABSTRACT Flame hardening method and apparatus for temperi gear teeth and the like which comprises quench mea for rapidly cooling selected ones of the gear teeth tc temperature which avoids the formation of decomp sition products. and -a heat source spaced from t quench means for raising the temperature of select ones ofthergear-teeth to a value which promotes t formation of an auste'nitic structure.

Mount means rotatably support the gear with select ones of the circumferentiallyextending teeth bei placed in heat'transi'er relationship with the he source andthe quench.

Index means rotate the gear an amount which mov one gear tooth from the heat source to the quenl means in a manner whereby all of the teeth of the ge must be'treated one time before any tooth can l treated a second time.

8 Clalms. 12 Drawing Figures PATENTEDJUN24 m5 SHEET MN nu PATENTEDJUN 24 ms l SHEET 2 3.091.191

FIG. \8 9) SHEET PATENTEDJUN24 I975 mm mm ON mm m: .hm

products. 4

It is often desirable especially on gears and sproekets, to harden ortemperthejouter marginal surface area of the teeth'and to leave the mainbody or central Q 1 g FLAME HARDENER,

BACKGROUND-OFTHE tNvENrtoN of ferrite, vpearlite, and bainite l-iypoeutectoid steels are quenchedfroma temperature inieacess of i600 F. whereas-hypereutectoid steels are vquenched froma' temperature in cxcessof 1340" F. Various alloys inhibit considerably slower cooling rates and. therefore is advantageousin hardening ofthicit pieces of st c eig Accordingiy, it is well known inthc art to heat treat I steels by heating the material to temperature inexcess of l670 F. and thereafter rapidly cooiing. th e metal so as to avoid theformation'of decomposition portion in an annearled or normalizedcondition. .The heat treated sprocket teeth will exhibit resistance to abrasive wear while-the untreatedmain central body.

portion of the sprocket will exhibit acrystalline structure comprised of a relativelysmaller, grain size. Hence, the sprocket main body portion will be free of stresses and less likely to develop cracks and other flaws during usage.

it is known to heat treat the entire sprocket by irn- 30 pinging a flame on the surface of the teeth so as to form austenitic steel, and to rapidly quench ther entire sprocket by submersion in a liquid, eith'erwater or oil.

This prior art hardening process is objectionable be; cause the central body portion of the sprocket acts as aheat sink, and accordingly, it too is heated sufficiently to lose its original ductility. Accordingly, it is desirable to be able to take advantage of the heat sink properties SUMMARY'OF T EiNvEN'noN for tempering selected areas of metallic goods, such as gear teeth, withoutdestroying the ductility of the main bodyportion of'the gear, I A heat source spaced from,afqu'erteh means simultaneously providesfor changingthe crystalline structure gear teeth are maintained "at a temperature level which avoids any change inthecrystalline'structure thereof.

A gear is rotatably mounted inindexed relationship with respect to the heat sourceand quench means so that each treated gear "tooth isiimmediateiyj totated from the heat source intothe quench, whereby each individual gear tooth must be heat trcated immediately receive a second heattreatment. v p a This sequential and cyclic treatment of the individual selected areas of the gear enablesanoutermarglnal surface area of each gear tooth to be heated to a temperature level which lies within the austenitic region, and then rapidly cooledto a temperature level which avoids the formation of. ferrite, peralitc,and, bainite;

" oad-treatment r 45 This invention relates to both method and apparatus.

' whileat the same time the remaining gear teeth anc central gear body are maintained at a tcmperaturc [which prevents change in its most desirable crystalline structure. h I

-. Therefore. a primary object'of the present inventior is the provision of method and apparatus for tempering selected portionsof metallic goods.

Another object of the invention isto provide meam by which metallic goods can be tempered so that a sei H I W b I l0 lected outer peripheraei marginal portion of the goods the formation of decomposition products and allow change in crystalline structure while the interior portion of the goodsretain their original crystalline struc ture.

r A further object 6r this invention i m provide 1 15 means for heat treating eylindrical metal goods by si multaneously, subjecting spaced selected areas of lht tothe action of an elevated and adepressed tem peraturefand cyclicly, quenching the' heated area whilr still another area is subjected to heat.

'IZ'A stillfurther objectof this invention is to disclose and provide apparatus for simultaneously subjecting spaced portionsof metallicj'goods to a heating anc theselected areas of the goods to be treated a first time before they can betreateda' second time.

v it Another and still further-object of this invention is t( provide apparatus for'cyc'iically heating, quenching and rotating a gear. with spaced. teeth of the gear being simultaneously subjected to a heating and cooling action, after-which. the gear is rotated in a mannci '.whereby each tooth being heated isvthereafter immediately quenched-withe all'of the teeth undergoing treat 5 ment before any one gear tooth can be treated a seconc time.

' v -.y, -5 'A n additional obiiectof. the present invention is tc ,ing a'fi'rs't'treat'ment beforeit can subjectedto a sec Thesefand' various and advantages. 0 the invention will.become ,readily apparent to thost skilled in the artguponreading the following dctaiict description:and eiaimsand ,by referring to the aceom panyi ng drawings., ,i

v are attainediinaccordance .witl theipresentjnvention by the;provision of a method 0 v y g I U heat treatingmetallic goods for usewith apparatus fab of one portion of the gear, teeth while. the remaining ricated in a 'manneti'substaritiailyas described in th a ove,sb 's wm v-l pater DESCitlPTiON or 'me DRAWlNGS a 1B forth a part schematical partdiagrarnm'atical, part cross-sectional representa tion of apparatus which sets forth the essence of th 60 present invention; .r followed by quenching before any onejgear-tooth can FIG. 2 is a perspective front view of onerform of ap paratus made in accordance with the diagrammatic: teachings of FIG. It i a FltJJis'an enlarged,fragmentary, perspective vie which discloses an upper rear portion of the apparatu y EIG 4 is a perspective'view which discloses the rigr side of theapparatus seen in FIG. 2;

3. FIG. isan enlarged, fragmentary. top perspective view of the apparatus disclosed in FIG. 4;'

FIG. 6 is an enlarged. .fragrnentary..side clevational view of part of the apparatus dis'closed in FlG .-2;

FIG. 7 is an end view of the: appar atus disclosed in FIG. 6;

FIG.'8 is a detailed. part cross-sectional;enlargedde apparatus fdisclosed in the one control circuitwhich can be used in conjunction with the apparatus disclosed in the foregoing figures.

DETAILED DESCRIPTION GFQTHE 'EMBODIMENTSQI FIG. IA discloses apparatus for carrying out the method of the present invention. The apparatus is comprised of mount means 115 for rotatably supporting a gear. and a heat source apparatu'sZlSfor heating se lccted areas of a gear. The mount r'neans'includes a mandrel or the like disposed along the axial line 16 and 1 includes releasable engaging means 17 so that a gear 18 can be rapidly mounted upon and removed from the mandrel in a commodious manner.

Quench means in the form of a fluid reservoir, having cross-sectional; en-

4 particularly a single horizontal row of teeth as seen in the present illustration.

Crank 33 is supported on a base of the machine and when rotated drives a link 34 fwhich oscillates a bell cranltl35, with the bell crank imparting limited reciprocatory rnotioninto the torch holder by means of a connecting; 136. I Limit switch 41' is. strategically placed to. be actuated by the movablemount plate so as to en- ,theretract cylinder. w 1 ,1 Throughout the remaining figures of the' drawings, wherever possible. like orsimilar elementswill be reable control of the action of the piston associated with l0 ferred to by like or similar numerals, and the foregoing numerals used in conjunction with FIG. IA will be found applied to like or equivalent elements in the remaining figures.

In the more specific embodiment of FIG.) 1B the mount means 20 is seen-to include a hollow mandrel 20 which has a free-marginal end portion to which :there is removably attached the before m entioned re-,

leasable en aging'means 1 7.

:Air'actuatedlair cylinder 21 has' the piston thereof a fluid level 19, is disposed in underlying relationship respective to the gear undergoing treatment, with "a lower marginal portion ofthe gear being immersed below the fluid level and'in heat conducting relationship respective to the reservoir liquid:

The mount means includes means byewhich thje" gear can be cyclicly rotated; Means 20 includes a main I T body portion 20 rigidly affix'edto the mandrel so that,

when the body is rotated,*theimandrel and gearmust move therewith. l

An air actuated cylinder 21 jltas thepiston thereof, journaled at 22 so that a crescent plate member, can

move independently of index plate member 23. The index plate is provided with a plurality of circumferentially' disposed apertures 24 about anouter marginal edge thereof. The last named apertures each cooperate with a plunger device 25 by receiving pin 26 thereinto when the pin is extended therefrom and inaxial alignment therewith. as will be explained in greater' detail later on in this'disclosure.

Air actuated gear release cylinder 27 has the piston thereof connected to a pilotrod means which extends through the central longitudinal axis of the hollow mandrel for actuating a releasable gear holder mechanism. the details of which will be better appreciated later 'on in this disclosure. Limit switch 28 is actuated, in response to movement of the crescent plate member and provides part of the automatic control apparatus of the present invention. t The heat source is comprised of a movable mount plate 29 which is advanced towards and away from the gear by an air actuated retractcylinder 30. A torch holder 31 is mounted for movement to the mount plate and has a plurality of spaced torch nozzles which provide an oxy-acetylene flame for direct impingement upon selected ones of theteeth of the g'ear,-or more joumaled at 22" to" the crescent platemember 48. The

crescentplate'member is rotatably journ'aled in captured relationship to the exterior surface. of the mandrel so that'it canbe independently turned about the central axis 16. Index plate member 23 is disposed adjacent to the'crecent plate member with'each plate memberfbeing arranged in-spaced vertical parallel planes.j I

Brake drumSl is affixed to. the mandrel and can be selectively engaged b'y the cooperatingbrake band 54 so that the mandrel is rendered non-rotatable while the brake assembly is engaged therewith.

a ltshould noted that thejheat source apparatus prefe'rablyf isprovided' withonetorch nozzlefor each wtooth of a r'owof tee'th.jThe 'co'nr'iectin'g'rod 36fenables the crank t'o impart reeiproc atory-motion' into the torch holder. w'hile'the r'etracti cylinder advances the torl ches into-heattransfertelationship respective to the w e ks! nd sq ns isst aw -As seen invarious o'nes'of theremaining figures, and

' in particular FIG. Zinconjunction with FIGS6 and 7,

5 connected to a downwardlyidepending car which is rigthe before mentioned 'conn'ecting'rod 36 is seen to be idly affixed to the torch holdermount plate so that oscillatory motion canbe'impart'ed-thereinto with the torch holder! reciprocating in captured relationship along shaft 37by means of low friction mount bushing 38, The "spaced parallelshafts 37 and 37' areheld in f'proper alignment r'espe'ctive'to one 'another'by mount blocks 39. The blocks are'rigidlyaffixed toplate member 29. Plate member'29 is-journaled to apair of forwardlyspa'ced struts andQasingle" rear'strut, 40 and 41.

respectlvelygfwith the struts more or less forming a parallelogram which isjoarnaledat eachcorner thereof so as to maintain 'the torch support'at a constant angle of attack as it is moved into close proximity'of and away from the gear. 1

. A link 42 ties the strut 40 to a lever ,43, with the pivoted end of the lever beingjournaled to an anchored upstanding fixed mount 44. The piston of the retract cylinder actuates the lever which lnturn imparts motion'into the parallelogram forfad'vancing and retracting the torch holder; t y

' As seen in FIGS. 8 and 9, in conjunction with other figures of the drawings."the crescent plate member 48 is rigidly affixed to a cylindrical housing 149 oflimited length. with the housing being rotatably arranged with respect to the mandrel so that the housing can move along a limited arcuate path' respective to'the bearing support housing 50 and to the index plate. Brake drum 51 is attached to the mandrel and moves therewith. The air cylinder 27 is attached at 52 so that it can swivel This action rotates the heated row of gear teeth in aposition underlying the liquid level of the quent means, and brings a' new row of untreated gear tec into alignment with the flame from the torches. Tl time lapse in cycling from a heating to a quenched co dition must occur rapidly enough to avoid the form with the indexplate assembly. Brake adjustmentSS is I received through the base plate 49 so that a brake band der 25 so that the illustrated lever thereof is captured between the spaced flanges 58 and 59 of the plunger device thereby causing the switch to be actuated in response to movement of the plunger pin 26.

As seen in H08. 18, 3, 5, and 10, the free end, or gear supporting end, of the mandrel has spaced flanges v6] and 62 rcmovably affixed-thereto with the coneshaped flanges having a removable adjustable cylindrical member 63 bearing thereagainst. Manual control valve assembly 127 actuates the air cylinder 27 causing the piston thereof to move the pilot rod 65 to thereby move the spaced flanges toward or away from one another so as to clamp'the gear in axial aligned relationship along the longitudinal axis 16.

Control box 67 protectingly contains part of the cir cuitry illustrated in FIG. 11 so that the operator of the Flame Hardening Machine can control theentire action of the apparatus from close proximity of the control box. The outer peripheral edge 68 of the quench tank preferably is a self-supporting monocoque struc-- tion of pearlite and other decomposition produc which tend to increase the ductility of the steel.

Since the lowermost marginal edge portion of u gear is always submerged within the quench means, an since the flame from the torches are played onto a St lected limited area represented by a width slight greater than a single horizontal row of teeth. it will no be appreciated that the massive body of the gear advai tageously provides a heat sink which maintains the ct tire gear, except for the high temperature region, at temperature below the austenite and cementite form; tin range so that only the'outermost marginal surfac area of the one row of teeth are subjected to a tempera ture of approximately I670 F. As to the rapid trans tion between i333 and'ambient temperature whic must occur somewhere. between the heat source an the quench, it is believed that the rapid temperatur gradient actually promotes the quality of the gear i that a limited amount'of annealing and stress relievin treatment is imparted into the gear at critical area: Stated differently, the gear teeth become austeniti with there being a rapid transition between the surfac of the teeth and the gear body, which retains its origin:

crystalline structure.

, proximately90 so that a new row of teeth are brougl into 'the heating region, while the heated teeth ar that the gear be rotated either seven or nine teet ture built up in a conventional manner. A hc'at'shield 69 has an arcuate portion 70 for protecting the main bearing support housing from the deleterious effects of the heat source.

Broadly, the operation of the flame hardening apparatus comprises placing a cylindrical metallic object, illustrated herein as a multi-toothed sprocket, and hereafter called a gear, onto a mandrel so that the lowermost marginal edge portion of the gear is submersed below the water level, and another marginal edge portion of the gear is placed sufflciently close to the torch nozzles so that combustion of hydrocarbons creates'a flame which impinges upon a row of gear teeth.

After the row ofteeth have been subjected to. the action of the flame for a sufficient amount of time to cause the metal thereof to be heated into the austenitic region, the actuating cylinder 30 retracts the movable mount plate into its alternate position. The plunger device then retracts plunger pin 26 from its associate aperture, and air cylinder 21 moves'the crescent plate 48 a limited arcuatc amountrclative to the mandrel. Next the plunger device 25 engagesthe plunger pen 26 with an aperture 24 with the last aperturebeing spaced about 90 from the former aperture. The cylinder 21 returns the urcuate plate to its original position, bringing the index plate therewith, and actuating cylinder returns the movable mount plate bearing the torches into heat transfer relationship respectiveto the row of gear teeth.

which is exactly 90pius or minus one tooth.

For example, numbering the teeth l-32, the sequer tial order of treatment is as follows: i, 8, i5, 22, 29. ll, 18, 25, 32, 7,14, 21, 28, 3, l0, i7. 24, 31,6,11 20, 27, 2, 9, i6, 23, 30, 5, l2, l9, and 26. Hence th index plate is arranged relative to the stops 55, 56 t cause each of the teeth to receive a first treatment bi fore any one tooth can receive a second treatment.

By carrying out several different possible sequenti: orders in which the teeth are treated. each tooth of th gear will receive one treatment before it could inadve tently receive a second treatment. With this in min any number of different programs could be set up, i for example, quenching and heating at angular dispt sitions otherthan the'before recited 90 plus or mint one row of teeth, depending upon the configuration the object being treated.

Where a plurality of adjacent rows of teeth must t simultaneously heated and quenched, the before St quential order of cyclic operation can still be observe I by considering dual or triple rows of adjacent teeth l areas receive one treatment before any one area can receive a second treatment.

Looking now more specifically to the details of the operation of the present apparatus, those skilled in the art should now appreciate that a gear 18 can be placed on the mandrel by removing the fastener means, selecting a spacer 63 of the proper length. telescopingiy sliding the gear against flange 61, after which the cone 62 is placed into engagement with the gear. whereupon shaft 65 can then be retracted by actuating air cylinder 27 with air control valve 127. This expedient rigidly mounts the gear so that it is properly located relative to the quench and to the heat source. Controller 67 is adjusted so that the duration of each cycle of treatment will attain a proper heat soak and additionally so that the apparatus will automatically be de-energized after the last row of teeth has been heat treated. The index plate 23 is selected to have the proper number of apertures therein. and stop means 55, 56 adjusted as may be required for proper operation of limit switch 28 in conjunction with the apertures of the index plate.

Automatic igniters can be provided for initiating a flame at the torches, so that when the apparatus is energized. cylinder 21 will be in the proper relative position and the actuating cylinder will move the mount plate forward to thereby move the torches so that the flame therefrom is properly positioned relative to a selected horizontal row of gear teeth. while motor 45 causes the torches to reciprocate relative to the mount plate. After a predetermined lapsed time. based upon experience for a particular size and composition of a gear, the controller apparatus causes the actuating cylinder to retract, pin 26 is retracted from the index plate, cylinder 21 rotates member 49 relative to the mandrel, pin 26 is returned into a different aperture 24, cylinder 21 returns member 49 to its original position, and since crescent plate 48 is tied to index plate 23 by means of the plunger pin, the mandrel must rotate between the limits provided by stop means 55,56. This action causes the gear to rotate approximately 90, depending upon the number of rows of teeth contained in the gear. Cylinder 30 returns the mount plate so that the flame from the torches is now in heat transfer relationship relative to a new row of teeth. The next cycle of operation has commenced and after another lapsed time, the apparatus will again cycle until the last remaining row of teeth have been heat treated an the controller turns off" the apparatus. At this time air control valve 127 is actuated thereby moving pilot shaft 65 so as to enable flange 64 and cylinder 63 along with cone 62 to be removed from the mandrel and another untreated gear placed upon the mandrel in the before described manner.

One means by which the present apparatus can be automatically controlled is set forth in FIG. 11 wherein those skilled in the art of reading pneumatic-hydraulic and electrical circuitry will recognize that a source of current must be provided at S so that current flows to S' and to the junctions 74, 75, 77, and 78. At this time the variable speed motor 45 and timing relay 87 are energized and the torches are moved into heat transfer relationship respective of the gear undergoing treatment.

After the first row of teeth has been heated the desired set time, timing relay 87 actuates the latching relay 81 to move air control valve 100 to a position which causes cylinder 30 to retract, thereby moving the torches away from the gear. As the cylinder 30 retracts it engages and moves switch 47 which energizes the cycle counter to indicate that the first row of gear teeth has completed its treatment.

The latching relay also moves the air control valve to a position which causes the latching cylinder 25 to retract pin 26. As pin 26 is retracted, it engages and moves switch 57'. which energizes air control valve 84, causing cylinder 2! to rotate the head until the stop 55 engages the switch 128, thereby causingthe latching relay 81 to return to its first or run position.

The return of the latching relay to its run position moves the air control valve 80 to a position which causes the cylinder 25 to extend pin 26 into an appropriate aperture of the index plate. As the pin is extended. switch 57 is returned to its run position which actuates air control valve 84 causing cylinder 21 to m tate the arcuate plate member of the control head back to the run or heat treating position, rotating the mandrel therewith.

As the arcuate plate member is returned. stop 156 thereof engages switch 128 which shifts the air control valve l00 causing cylinder 30 to extend the torches into heat transfer relationship respective to the gear undergoing treatment.

The timing relay commences to time out, as the next cycle of operation begins. The automatic control circuitry continues the above cyclic operation until the last row of teeth is treated, whereupon the apparatus is "shut down" so that the treated gear can be replaced with a gear which is to be heat treated in the same above described manner.

I claim:

1. Flame hardening apparatus for tempering gear teeth comprising:

quench means for rapidly cooling a gear tooth to a temperature which avoids the formation of decomposition products; a heat source for raising the temperature of a gear tooth to a temperature which promotes the formation of an austenitic structure; mount means for rotatably supporting a gear wherein the gear has circumferentially spaced gear teeth thereon which are to be simultaneously placed in heat transfer relationship with said quench means and said heat source;

said heat source and said quench means being circumferentially spaced about said mount means so that the teeth of a gear supported by said mount means has one tooth thereof in heat transfer contact relationship with said heat source, another tooth thereof in heat transfer contact relationship with said quench means, and with there being a plurality of teeth located between said one tooth I and said another tooth;

means for rotating said mount means an amount which moves the one gear tooth directly from the heat source to the quench means; said means for rotating said mount means includes an index means, said index means being connected to cause a gear supported on said mount means to be rotated an amount equal to the circumferential distance about the gear measured from said heat source to said quench means so that each and every time the index means causes a gear to be rotated a tooth of the gear is moved directly from the heat source to the quench means; said index means further providing that all of the individual gear teeth are subjected to the action of the heat source and quench means a single time before any one tooth can be subjected to the action of the heat source and quench means a second time.

2. The flame hardening apparatus of claim I wherein said mount means includes an elongated journaled shaft having an index plate member affixed to a free end thereof and the gear removably affixed at the other end thereof;

a housing journaled to said shaft, said housing having a pin member engagable with said index plate member so that movement of said housing rotates said index plate, means cyclically rotating said housing an amount which turns said shaft to move the gear through an angle to move a tooth from the heat source into the quench means.

3. The flame hardening apparatus of claim 2 wherein said shaft is hollow, and further including a mandrel extending therethrough and through said index plate member means affixed to said index plate member for moving said mandrel relative to shaft, fastener means for releasably attaching a gear to the end of said shaft, and means by which movement of said mandrel releases the gear from said fastener means.

4. The apparatus of claim 1 wherein said heat source is provided by a plurality of torches. a platform, said plurality of torches being attached to said platform, said platform being movable from a first to a second position which places any flame which may be provided by the torch adjacent to the gear tooth and removes the flame from the torch from the gear tooth; and, means for moving said torches laterally of said platform so that the flame can oscillate relative to the gear tooth.

5. Apparatus for flame hardening gear teeth comprising a quench means in the form of a water containing tank for rapidly cooling a flank of gear teeth; means forming a heat source for raising the temperature of another flank of gear teeth;

mount means for rotatable supporting a gear with one flank of teeth being placed in heat transfer relationship respective to the quench means and another flank of teeth being disposed in heat transfer relationship respective to the heat source, and with said quench means and heat source being spaced apart an amount to allow a plurality of flanks of teeth to be interposed between said one flank and said another flank of teeth; means for selectively rotating said mount means an amount which moves the location of said one flank of teeth to the location of said another flank of teeth, said means for selectively rotating including a housing, a shaft journaled for axial movement, releasable engaging means for rapidly mounting a gear to said shaft; said shaft having an index plate member attached to one end thereof and a marginal length thereof received within said housing;

another plate member rotatably mounted for movement about said shaft, means for rotating said an other plate member from a first to a second position, a plunger device mounted on said another plate member and movable into engagement with said index plate member so that when said plunger engages said index plate member and said another plate member is moved, the index plate member must move a corresponding amount;

. brake means connected to arrest movement of said index plate member, and means actuating said brake means when said plunger is moved from engagement with said index plate member.

6. The apparatus of claim 5 wherein said quench means is a liquid bath underlying said mount means and having a liquid level arranged relative to said mount means so that a gear supported on said mount means has at least one flank of teeth submersed below the liquid level.

7. The apparatus of claim 5 wherein said heat source is a torch means for providing controlled combustion products for producing a flame and includes a plat form, said platform being movable from a first to a second position, respectively, in order to place the flame adjacent to the outer surface area of the flank of teeth and which removes the flame to a position remote from the flank of teeth, respectively; and,

means for moving said heat source laterally of said platform so that the flame can oscillate relative to the flank of teeth.

8. The apparatus of claim 7 and further including control means comprised of an actuator for said plunger, an actuator for said platform, an actuator for said plate member;

timer means connected to cause said actuator to advance said platform, and after a time delay in which the gear is heated to form an austenitic structure along the surface of the flank of teeth being heated, said actuator for said plate member is moved to position said plunger adjacent to said index plate, thereby causing said platform to retract while said plunger engages said index plate, causing said plate member to move said index plate from the recited location which causes the heated flank of teeth to be moved into said quench;

and thereafter said platform is returned into close proximity of the gear.

i i i t 

1. Flame hardening apparatus for tempering gear teeth comprising: quench means for rapidly cooling a gear tooth to a temperature which avoids the formation of decomposition products; a heat source for raising the temperature of a gear tooth to a temperature which promotes the formation of an austenitic structure; mount means for rotatably supporting a gear wherein the gear has circumferentially spaced gear teeth thereon which are to be simultaneously placed in heat transfer relationship with said quench means and said heat source; said heat source and said quench means being circumferentially spaced about said mount means so that the teeth of a gear supported by said mount means has one tooth thereof in heat transfer contact relationship with said heat source, another tooth thereof in heat transfer contact relationship with said quench means, and with there being a plurality of teeth located between said one tooth and said another tooth; means for rotating said mount means an amount which moves the one gear tooth directly from the heat source to the quench means; said means for rotating said mount means includes an index means, said index means being connected to cause a gear supported on said mount means to be rotated An amount equal to the circumferential distance about the gear measured from said heat source to said quench means so that each and every time the index means causes a gear to be rotated a tooth of the gear is moved directly from the heat source to the quench means; said index means further providing that all of the individual gear teeth are subjected to the action of the heat source and quench means a single time before any one tooth can be subjected to the action of the heat source and quench means a second time.
 2. The flame hardening apparatus of claim 1 wherein said mount means includes an elongated journaled shaft having an index plate member affixed to a free end thereof and the gear removably affixed at the other end thereof; a housing journaled to said shaft, said housing having a pin member engagable with said index plate member so that movement of said housing rotates said index plate, means cyclically rotating said housing an amount which turns said shaft to move the gear through an angle to move a tooth from the heat source into the quench means.
 3. The flame hardening apparatus of claim 2 wherein said shaft is hollow, and further including a mandrel extending therethrough and through said index plate member means affixed to said index plate member for moving said mandrel relative to shaft, fastener means for releasably attaching a gear to the end of said shaft, and means by which movement of said mandrel releases the gear from said fastener means.
 4. The apparatus of claim 1 wherein said heat source is provided by a plurality of torches, a platform, said plurality of torches being attached to said platform, said platform being movable from a first to a second position which places any flame which may be provided by the torch adjacent to the gear tooth and removes the flame from the torch from the gear tooth; and, means for moving said torches laterally of said platform so that the flame can oscillate relative to the gear tooth.
 5. Apparatus for flame hardening gear teeth comprising a quench means in the form of a water containing tank for rapidly cooling a flank of gear teeth; means forming a heat source for raising the temperature of another flank of gear teeth; mount means for rotatable supporting a gear with one flank of teeth being placed in heat transfer relationship respective to the quench means and another flank of teeth being disposed in heat transfer relationship respective to the heat source, and with said quench means and heat source being spaced apart an amount to allow a plurality of flanks of teeth to be interposed between said one flank and said another flank of teeth; means for selectively rotating said mount means an amount which moves the location of said one flank of teeth to the location of said another flank of teeth, said means for selectively rotating including a housing, a shaft journaled for axial movement, releasable engaging means for rapidly mounting a gear to said shaft; said shaft having an index plate member attached to one end thereof and a marginal length thereof received within said housing; another plate member rotatably mounted for movement about said shaft, means for rotating said another plate member from a first to a second position, a plunger device mounted on said another plate member and movable into engagement with said index plate member so that when said plunger engages said index plate member and said another plate member is moved, the index plate member must move a corresponding amount; brake means connected to arrest movement of said index plate member, and means actuating said brake means when said plunger is moved from engagement with said index plate member.
 6. The apparatus of claim 5 wherein said quench means is a liquid bath underlying said mount means and having a liquid level arranged relative to said mount means so that a gear supported on said mount means has at least one flank of teeth submersed below the liquid level.
 7. The apparatus of claim 5 wherein said Heat source is a torch means for providing controlled combustion products for producing a flame and includes a platform, said platform being movable from a first to a second position, respectively, in order to place the flame adjacent to the outer surface area of the flank of teeth and which removes the flame to a position remote from the flank of teeth, respectively; and, means for moving said heat source laterally of said platform so that the flame can oscillate relative to the flank of teeth.
 8. The apparatus of claim 7 and further including control means comprised of an actuator for said plunger, an actuator for said platform, an actuator for said plate member; timer means connected to cause said actuator to advance said platform, and after a time delay in which the gear is heated to form an austenitic structure along the surface of the flank of teeth being heated, said actuator for said plate member is moved to position said plunger adjacent to said index plate, thereby causing said platform to retract while said plunger engages said index plate, causing said plate member to move said index plate from the recited location which causes the heated flank of teeth to be moved into said quench; and thereafter said platform is returned into close proximity of the gear. 